Shi Peng, Du Luping, Yuan Xiaocong
Opt Express. 2018 Sep 3;26(18):23449-23459. doi: 10.1364/OE.26.023449.
We investigate the spin properties of a family of cylindrical vector vortex beams under a focusing condition. The spin-orbit interaction is demonstrated by comparing the energy flow and spin flow density of the focused field to those of the incident field. This spin-orbit interaction is analyzed to construct the desired distribution of spin angular momentum for optical manipulation. The structured spin angular momentum of the focused field can transfer to the optical torque for the non-magnetic absorptive particle. The influences of polarization topological charge, vortex topological charge and wavelength on optical torque in the hot-spot of focused field are summarized for three typical particles. Such results may be exploited in practical optical manipulation, particularly for optically induced rotations.
我们研究了一族圆柱矢量涡旋光束在聚焦条件下的自旋特性。通过将聚焦场的能流和自旋流密度与入射场的进行比较，证明了自旋-轨道相互作用。对这种自旋-轨道相互作用进行分析，以构建用于光学操控的自旋角动量的期望分布。聚焦场的结构化自旋角动量可以转移到非磁性吸收粒子的光学扭矩上。针对三种典型粒子，总结了偏振拓扑电荷、涡旋拓扑电荷和波长对聚焦场热点处光学扭矩的影响。这些结果可应用于实际的光学操控，特别是用于光致旋转。
